Steiner Cephalometric Analysis
Marcello M. | August 17, 2026
A Complete Guide for Orthodontic Diagnosis and Treatment Planning
Orthodontic Diagnosis & Cephalometrics
The Steiner cephalometric analysis remains one of the most widely recognized cephalometric approaches in orthodontics. Its strength lies in its relatively simple interpretation of skeletal, dental, and soft-tissue relationships.
Introduction
Cephalometric analysis has played a major role in orthodontic diagnosis for decades. By transforming a lateral cephalometric radiograph into a standardized set of anatomical landmarks, reference planes, angular measurements, and linear measurements, the orthodontist can evaluate the sagittal and vertical relationships between the cranial base, maxilla, mandible, and dentition.
Among the classical cephalometric analyses, the Steiner analysis remains particularly influential because of its practical organization and its emphasis on the relationship between skeletal structures, incisor position, and soft-tissue profile.
The analysis is commonly used to evaluate:
- Maxillary sagittal position
- Mandibular sagittal position
- Maxillomandibular skeletal discrepancy
- Vertical skeletal relationships
- Upper and lower incisor position
- Interincisal relationship
- Soft-tissue profile
However, Steiner measurements should never be interpreted in isolation. Modern orthodontic diagnosis requires integration of clinical examination, facial analysis, photographs, dental casts or digital models, radiographic information, growth assessment, periodontal considerations, and the patient's treatment objectives.
1. Historical Background of the Steiner Analysis
The Steiner analysis became one of the classic approaches to orthodontic cephalometrics because it attempted to connect cephalometric measurements with clinical treatment planning.
Rather than simply describing craniofacial morphology, the Steiner approach was designed to provide the clinician with a framework for understanding the skeletal discrepancy, dental compensation, and soft-tissue consequences of orthodontic treatment.
This treatment-oriented philosophy is one reason why Steiner's analysis has remained widely taught and clinically relevant despite the development of numerous other cephalometric systems.
2. Essential Cephalometric Landmarks
Correct landmark identification is the foundation of any cephalometric analysis. Errors in landmark identification can directly affect the calculated measurements.
Sella (S)
Sella represents the midpoint of the sella turcica. It is used as a reference point for the anterior cranial base and forms part of the S-N reference line.
Nasion (N)
Nasion is the most anterior point of the frontonasal suture in the midsagittal plane. It is an important reference landmark for several angular measurements, including SNA, SNB, and ANB.
Point A
Point A, or subspinale, represents the deepest concavity on the anterior contour of the maxillary alveolar process.
It is used to describe the sagittal position of the maxilla relative to the cranial base.
Point B
Point B, or supramentale, represents the deepest concavity on the anterior contour of the mandibular symphysis.
It is used to evaluate the sagittal position of the mandible.
Pogonion (Pog)
Pogonion represents the most anterior point of the bony chin. It contributes to the evaluation of mandibular morphology and is particularly useful when considering the relationship between the lower incisors and the mandibular symphysis.
Gnathion (Gn)
Gnathion is a constructed point located approximately midway between the most anterior and most inferior points of the mandibular symphysis.
It can be used in the assessment of vertical mandibular relationships.
Gonion (Go)
Gonion represents a constructed point at the angle of the mandible and is used in defining the mandibular plane in Steiner-type analyses.
3. The Main Reference Planes
Sella-Nasion Plane (SN)
The S-N line connects Sella and Nasion and is commonly used as a reference for evaluating the sagittal position of the jaws.
Because it represents a cranial base reference, changes in the orientation and length of the cranial base can influence measurements based on the SN plane.
Mandibular Plane
The mandibular plane is used to evaluate vertical skeletal relationships. In Steiner analysis, the mandibular plane is commonly represented by the Go-Gn line.
NA and NB Lines
The NA line connects Nasion and Point A, while the NB line connects Nasion and Point B.
These lines provide the reference for evaluating the position and inclination of the upper and lower incisors.
4. Skeletal Analysis
4.1 SNA Angle
SNA is the angle formed by the Sella-Nasion line and the Nasion-Point A line.
It is primarily used to estimate the anteroposterior position of the maxilla relative to the anterior cranial base.
A higher SNA value may be associated with a relatively anterior maxillary position, whereas a lower value may suggest a relatively posterior maxillary position.
However, an abnormal SNA value should not automatically be interpreted as maxillary prognathism or retrognathism. The measurement is influenced by cranial base morphology and the position of Nasion.
4.2 SNB Angle
SNB is the angle formed by the Sella-Nasion line and the Nasion-Point B line.
It is used to estimate the sagittal position of the mandible relative to the anterior cranial base.
A relatively increased SNB may be associated with a more anterior mandibular position, while a reduced SNB may suggest a relatively posterior mandibular position.
Again, the measurement should be interpreted together with facial examination and other skeletal parameters.
4.3 ANB Angle
The ANB angle is obtained by subtracting SNB from SNA.
It is traditionally used as an indicator of the sagittal relationship between the maxilla and mandible.
A larger ANB value is generally associated with a skeletal Class II relationship, whereas a smaller or negative value may be associated with a skeletal Class III relationship.
ANB is one of the most frequently used cephalometric measurements in orthodontics. However, it has important geometric limitations.
5. Why ANB Should Not Be Used Alone
One of the most important concepts when interpreting Steiner analysis is that ANB is not a direct measurement of the skeletal discrepancy between the maxilla and mandible.
The value of ANB can be influenced by several geometric factors, including:
- The anteroposterior position of Nasion
- The vertical position of Nasion
- The relative positions of Points A and B
- Facial divergence
- Rotation of the jaws
- Vertical facial morphology
Research has demonstrated that ANB may not adequately represent the true anteroposterior skeletal discrepancy in some patients. Geometric effects involving Nasion, the occlusal plane, and the relative positions of the jaws can significantly influence the measurement.
For this reason, ANB should be interpreted alongside the clinical facial pattern and, when appropriate, alternative measurements such as the Wits appraisal.
6. Steiner Analysis and the Wits Appraisal
The Wits appraisal was developed partly in response to limitations associated with the ANB angle.
Instead of using Nasion as the central reference point, the Wits appraisal projects Points A and B onto the occlusal plane.
This provides an alternative assessment of the anteroposterior relationship of the jaws.
Neither ANB nor Wits should automatically be considered the definitive measurement. The two parameters can provide complementary information when interpreted in the context of facial morphology.
Studies examining the relationship between ANB and Wits have demonstrated that both measurements are influenced by geometric and identification factors, reinforcing the need for a multidimensional interpretation. :contentReference[oaicite:2]{index=2}
7. Vertical Skeletal Analysis
Steiner analysis also incorporates parameters that help characterize the vertical facial pattern.
SN-GoGn
The angle between the Sella-Nasion plane and the mandibular plane is commonly used to assess mandibular divergence.
A relatively increased value may be associated with a hyperdivergent facial pattern, while a lower value may be associated with a hypodivergent pattern.
This parameter can provide useful information when evaluating:
- Deep bite tendencies
- Open bite tendencies
- Mandibular rotation
- Vertical facial proportions
- Growth pattern
However, vertical diagnosis should never depend on a single angular measurement. Facial height, mandibular plane orientation, lower anterior facial height, and clinical examination should also be considered.
8. Dental Analysis
One of the strengths of the Steiner analysis is its detailed evaluation of incisor position relative to the skeletal bases.
8.1 Upper Incisor to NA
The upper incisor is evaluated relative to the NA line using both an angular and a linear measurement.
The angular measurement evaluates the inclination of the upper incisor relative to the NA line, while the linear measurement describes the anteroposterior position of the incisor relative to the NA line.
Using both measurements is important because two patients may have similar angular values but different incisor positions, or vice versa.
8.2 Lower Incisor to NB
The lower incisor is evaluated relative to the NB line using:
- L1-NB angle
- L1-NB linear distance
These parameters help determine lower incisor inclination and sagittal position.
They are particularly useful when assessing dental compensation in skeletal Class II and Class III malocclusions.
8.3 Interincisal Angle
The interincisal angle describes the relationship between the long axes of the upper and lower incisors.
It provides an overall assessment of incisor inclination and can be useful in evaluating excessive proclination, retroclination, or incomplete torque control.
However, the interincisal angle does not describe the position of the incisors relative to the skeletal bases and should therefore be interpreted alongside U1-NA and L1-NB measurements.
9. Dental Compensation in Skeletal Malocclusion
One of the most clinically useful concepts in Steiner analysis is the relationship between skeletal discrepancy and dental compensation.
For example, a patient with a skeletal Class II relationship may develop compensatory changes in incisor inclination. Similarly, a skeletal Class III relationship may be accompanied by compensatory proclination of the upper incisors and retroclination of the lower incisors.
These dental compensations can partially mask the underlying skeletal discrepancy on clinical examination.
Consequently, the orthodontist must distinguish between:
- The underlying skeletal discrepancy
- The dental compensation
- The treatment-induced dental movement
This distinction becomes particularly important when planning orthodontic camouflage versus orthognathic surgery.
10. Soft-Tissue Analysis
A major contribution of Steiner's approach was the consideration of the soft-tissue profile in treatment planning.
Dental movements influence the position of the lips and therefore may affect facial profile aesthetics.
The soft-tissue analysis should include assessment of:
- Upper lip position
- Lower lip position
- Chin prominence
- Nasolabial relationship
- Facial convexity
- Incisor-lip relationship
A cephalometric treatment plan that achieves ideal skeletal and dental measurements but produces an undesirable facial profile should be reconsidered.
11. From Cephalometric Analysis to Treatment Planning
The most important clinical use of Steiner analysis is not the production of a collection of numbers. Its real value is the integration of these measurements into a coherent treatment plan.
A useful sequence is:
- Evaluate the facial pattern clinically.
- Assess the skeletal sagittal relationship.
- Evaluate vertical skeletal morphology.
- Assess upper and lower incisor position.
- Identify dental compensation.
- Evaluate the soft-tissue profile.
- Determine the discrepancy between the current condition and the treatment objectives.
- Assess whether the desired movements are biologically and mechanically achievable.
This prevents cephalometric analysis from becoming a purely numerical exercise.
12. Limitations of the Steiner Analysis
Although Steiner analysis remains clinically useful, several limitations must be recognized.
12.1 Normative Values Are Not Universal
Cephalometric norms are population-dependent. Differences in ethnicity, sex, age, facial pattern, and craniofacial morphology can influence the expected values.
Studies of different populations have demonstrated significant differences in Steiner measurements, illustrating why normative values should not be treated as universal biological targets.
12.2 Two-Dimensional Representation
A lateral cephalogram compresses a three-dimensional craniofacial structure into a two-dimensional image.
Asymmetries, transverse discrepancies, and three-dimensional relationships may therefore be inadequately represented.
12.3 Landmark Identification Error
Some cephalometric landmarks are easier to identify than others. Small differences in landmark location can alter the resulting angular or linear measurement.
This is particularly relevant when measurements are used to make treatment decisions based on small differences from a reference value.
12.4 Treatment Prediction
One of the historical attractions of Steiner analysis was its attempt to assist with prediction of treatment changes.
However, research evaluating Steiner prediction has shown that the predicted changes for parameters such as ANB, U1-NA, L1-NB, and Pog-NB were not sufficiently accurate to serve as the sole basis for orthodontic treatment decisions.
This is an important distinction: cephalometric analysis can support treatment planning, but it cannot perfectly predict biological treatment response.
13. Manual Versus Digital Steiner Analysis
Digital cephalometric tracing has progressively replaced traditional manual tracing in many orthodontic practices.
Digital systems can improve workflow efficiency and allow automatic calculation of multiple parameters.
However, digital measurement does not automatically eliminate measurement error. The identification of anatomical landmarks remains a critical component of the analysis.
Studies comparing manual and digital Steiner tracing have found differences in some measurements, although digital methods can substantially reduce tracing time. More recent research continues to investigate the reliability of automated and AI-assisted cephalometric analysis.
The practical implication is that clinicians should understand the underlying landmarks and measurements even when using fully digital workflows.
14. Artificial Intelligence and Steiner Analysis
Artificial intelligence is increasingly being incorporated into cephalometric analysis.
Automated systems can identify landmarks, calculate measurements, and generate cephalometric reports in a fraction of the time required for manual tracing.
However, speed should not be confused with clinical accuracy.
Recent research has demonstrated that automated systems may show systematic differences from expert manual measurements, particularly for clinically important variables such as ANB and vertical measurements.
AI should therefore currently be regarded as a tool that assists the orthodontist, rather than a replacement for clinical interpretation.
15. How to Interpret a Steiner Analysis in Clinical Practice
Consider a hypothetical patient presenting with:
- Increased ANB
- Reduced SNB
- Relatively normal SNA
- Increased lower incisor inclination
- Increased upper incisor inclination
- Convex facial profile
A simplistic interpretation would be: "Skeletal Class II with proclined incisors."
A more complete interpretation would ask:
- Is the increased ANB caused primarily by mandibular retrusion?
- Is Nasion positioned in a way that influences the ANB?
- Is the patient hyperdivergent or hypodivergent?
- Are the incisors already compensating for the skeletal discrepancy?
- What is the soft-tissue profile?
- What amount of dental movement is biologically possible?
- Would orthodontic camouflage provide an acceptable facial result?
- Is orthognathic surgery indicated?
This illustrates the difference between measuring a patient and diagnosing a patient.
16. Practical Steiner Analysis Checklist
| Domain | Measurement | Clinical Question |
|---|---|---|
| Skeletal | SNA | Where is the maxilla positioned relative to the cranial base? |
| Skeletal | SNB | Where is the mandible positioned relative to the cranial base? |
| Skeletal | ANB | What is the sagittal jaw relationship? |
| Vertical | SN-GoGn | What is the mandibular divergence pattern? |
| Dental | U1-NA | How are the upper incisors positioned relative to the maxilla? |
| Dental | L1-NB | How are the lower incisors positioned relative to the mandible? |
| Dental | Interincisal angle | What is the relationship between upper and lower incisor inclination? |
| Soft tissue | Soft-tissue profile | How does the dentoskeletal pattern affect facial aesthetics? |
Clinical Relevance
Steiner analysis remains valuable because it provides a structured framework for linking skeletal morphology, dental compensation, and facial aesthetics.
Its greatest strength is its simplicity. Its greatest weakness is the temptation to interpret its measurements as absolute diagnostic truths.
The orthodontist should therefore use Steiner analysis as part of a multidimensional diagnostic process.
A patient should never be classified as skeletal Class II or Class III solely on the basis of ANB. Similarly, an incisor should not automatically be considered "incorrectly positioned" simply because its measurement differs from a published norm.
The clinical context always comes first.
Key Takeaways
- SNA evaluates the sagittal position of the maxilla relative to the cranial base.
- SNB evaluates the sagittal position of the mandible relative to the cranial base.
- ANB provides an estimate of the sagittal relationship between the maxilla and mandible but has important geometric limitations.
- U1-NA evaluates upper incisor position and inclination.
- L1-NB evaluates lower incisor position and inclination.
- The interincisal angle provides information about the relationship between upper and lower incisor inclination.
- Vertical measurements help identify the patient's facial divergence pattern.
- Soft-tissue analysis is essential when evaluating the aesthetic consequences of orthodontic treatment.
- Cephalometric norms should be interpreted according to the patient's individual facial morphology.
- ANB should ideally be interpreted together with clinical examination and, when appropriate, alternative sagittal assessments such as Wits appraisal.
- Digital and AI-based tracing can improve efficiency but do not eliminate the need for clinical judgment.
Conclusion
The Steiner cephalometric analysis remains one of the classic tools of orthodontic diagnosis. Its continued relevance comes from its ability to connect skeletal relationships, dental compensation, and facial aesthetics within a relatively simple analytical framework.
However, modern orthodontics requires a more sophisticated interpretation than simply comparing measurements with normative values.
The most clinically meaningful approach is to use Steiner analysis to identify patterns, generate hypotheses, and support treatment planning while integrating the findings with the patient's facial appearance, clinical examination, growth status, dental compensation, periodontal limits, and treatment objectives.
Cephalometric analysis should quantify the diagnosis — not replace the diagnosis.
Selected PubMed References
- Steiner cephalometric analysis: predicted and actual treatment outcome compared. Orthod Craniofac Res. 2006. PMID: 16764682 .
- Navarro ACL, Carreiro LS, Rossato C, Takahashi R, de Oliveira Lima CE. Assessing the predictability of ANB, 1-NB, P-NB and 1-NA measurements on Steiner cephalometric analysis. Dental Press J Orthod. 2013;18(2):125-132. PMID: 23916442 .
- Clinical application of a method to correct angle ANB for geometric effects. PMID: 3479897 .
- The relationship and reproducibility of angle ANB and the Wits appraisal. PMID: 1931857 .
- Manual tracing versus smartphone application (app) tracing: a comparative study. PMID: 28793813 .
- Comparative Evaluation of Digital Cephalometric Tracing Applications on Mobile Devices and Manual Tracing. PMID: 38909276 .
- Mobile-Based Digital and Manual Steiner Cephalometric Analysis: A Comparative Study of Accuracy and Efficiency. Eur J Dent. 2026. PMID: 42419699 .
Related Orthodontic Articles
- How to Interpret SNA, SNB and ANB in Clinical Practice
- Wits Appraisal vs ANB: Which Measurement Is More Reliable?
- Cephalometric Analysis in Skeletal Class II Malocclusion
- Cephalometric Analysis in Skeletal Class III Malocclusion
- Vertical Facial Pattern: SN-GoGn, FMA and Clinical Interpretation
- Upper and Lower Incisor Position: U1-NA and L1-NB Explained